Manufacture of milk-powder.



U NITED STATES PATENT oFFroE.

ADOLF GLAS, OF BERLIN, GERMANY MANU ACTURE OF MILK-POWDER.

No. 843,938. Specification of Letters Patent. Patented Feb. 12, 1907.

-Application filed June 20, 1904. Serial No. 213,382.

To all whom it may concern: 1 powder be completely dissolved, from nat- Be it known that I, An'oLF GLAS, a subject ural milk in this respect, that a considerable of the King of Prussia, and resident of Berpercentage of the lin,.Germany, have invented certain new and sziriace and forms a molten layer of yellowuseful Improvements in the M&I1' ,f8.0l31116 of i ish color-that is to say, the nature of the fat Milk-Powder, of which the following is a which is contained in ordinary milk in the specification. 1 shape of globules of varying size has been al- This invention relates to improvements in tered by the drying process, partly under the the manufacture of milk-powder, and coninfluence of heat, causing a large proportion, sists in an improved method of production,

which sometimes amo'..nts to ninety per cent., whereby is obtained a milk-powder which on i of the fatglobi:.les to coalesce, and partly to belng dlssolved in hot water will show all the i the fact that the coating of the globules has characteristics of freslimilk, with the same been destroyed. This alteration of the hyshomogeneity of the constituent arts, includical properties of the fat is the cazse of t e ining the butte -fat, as is fozzn in ordinary ferior keeping qrality of milk-powder made milk, and which in its dry state will not trrn from ordinary milk and of the separation of rancid, but willkeep sweet for aconsiderable the fat from the other constituents of the length of time, even exposed to the influmilkwhich remain in suspension. This tro ence'of humidity or air. To this end rior to 'ble is experienced with every known drying the drying operation I subject the mil or the rocess, whether the drying be effected at cream contained in milkto mechanical treatliigh or low temperatures, in the open or in ment serving to disintegrate the fat-globules, vacuum, on trays or on heated cylinders, or so that the milk' or the cream when evapoe by spraying the liqr id into a current of hot rated will contain the fat in the form of miair. Whichever of these operations be utilnute particles each enveloped in the other ized, however, for the process of drying, the solid constituents, and so protected from the preliminary operation of breaking up the fatglobules prevents in all cases the separation of fat in the shape of a molten layer when the powder is again dissolved. This result is unexpected, inso far as it might have been thought that the complete breaking up of the coating surroundin the fat-globules would have-made it muc easier for the fat particles to coalesce.

Instead of homogenizing the whole milk and then. drying the same I sometimes prefor to first separate the milk into skim-milk and cream by means of an ordinary centrifugal separator or the-like, then homogenize the POlTlOIl containing the cream, and thereafter dry the skim-milk and the cream either together or separately.

The utility of the invention will be evident ,from consideration of the circumsance that the demand for milk-powder is due to the difficulty or impossibility of keeping liquid milk in good condition for any length of time and that a powder produced by my process can be transported and stored wherever it is wan-ted, no.v- 'ithstanding the existence of those climatic, conditions which render the use of milk-powder desirable or neeair.

The disintegration of the fat articles may be effected by one of the so-called homogenizing or fixing machines, (for instance, themachine described in the specification of Letters Patent No. 756,053, of Gaulin,) in which the liquid milk is driven through very narrow passages and flows onto a springressed cone, so that the fat-globules are roken'up, or. in which the milk is squeezed between plates pressed into close proximity with one another or the like. Such homogenizing-machines are well known, and as the invention in no wise relates to the construction of such a machine no frrther description of the same is required. Milk thus homogenized contains the fat in astate of very fine division, the diameter of the particles being reduced to about 0.0008 centimeters. I now dry this homogenized milk, and so obtain milk-powder showing the abov -mentioned characteristics.

If ordinary milk .is dried by any known method toform, powder and if such powder be afterward dissolved or mixed with hot water, the resultant liquid diil'ers, even if'tho lat instantly rises to the essary and-negative't-he possibility of using non-durable powder.

It is to be observed that the process can be carried out by apparatus presently in use, although the steps of homogenizing and drying milk have nothing in common with each other and are in no sense correlated so as to render the invention obvious to one skilled in the art.

The improved powder resulting from the process is chemically the same aszany=other pure :powder obtained sfrom milk; but ,its

physical properties are Widely different.

Reconsiituted :milk behaves difl'erently from'natural milk, especially asregards the action of the fat particles,.and;it could not have been foreseen merely byobservationof the behavior of ordinary homogenized milk that suchresults would be-realized in a milkpowder or in a liquidreconstitutedfrom the same. 7

It-is-to be understood-that by the operation of'homogenizing is meant minutely subdividing the fat-globules by an-operat-ioninvolving a high-pressure. In the case of a machine'such as described in .Patent No. 756,953 this pressure varies fromtwo thundredto three hundredatmospheres.

ticles are completely enveloped by the other solid constituents of the as set forth.

A dry homogenized milk-powder containing substantially the same proportion of butter-fat as is'contained by Whole or unskimmed milk and in which milk-powder the fat particles are in a state of fine'subdivision and are completely'envelo ed by the ot-her solid cons tituentszol' lthe' mil vso-as tobe protected from the air, substantially as set milk, substantially .forth.

In testimony whereof I have "signed my name to this s'pecilicat-ionLin-the presence/of two subscribing 'witnesses.

' ADOLF 'GLAS.

- Witnesses;

HENRY "HASPER, WOLDEMAR 'HAUPT. 

